Rheostat



Nov. 20, 1928. f v 1,691,916 I A. C. BRADY RHEOSTAT Filed Feb. 26, 1927 avwentoz Mk6 HMO (Mugs now known.

' very novel structure which is readily adapted Patented Nov. 20, 1928.

amass-mes PATENT mes.

ARTHUR, d. BRADY,- or BRooxLY'mnEw YORK, Assreno'n 'ro CHAS. rnnsnman co.

INC., OF NEW YORK, N. Y., A

CORPORATION- OF I FEW YORK.

RHEOSTAT.

Application filed February 26, 1927. Serial No. 171,167.

This invention relates to current varying devices such as rheostats.

One of the objects of this invention is the provision of a novel form of rheostat which is very simple in structure, and is composed of relatively few'elements or parts.

A further object of this invention is the construction of a rheostat which is simple and easy to manufacture, and which is relatively inexpensive to produce. A still further object of this invention is the provision of a rheostat of rugged construction, and particularly adapted for use in radio sets.

These, as well as many other objects, are secured by means of my novel construction.

This invention resides substantially in the combination, construction, arrangement, and

relative location of parts, as will appear moreil ully hereinafter.

Referring to the drawings, in which the same reference numerals will be used wherever possible to indicate the same or similar parts in the different views,

1 represents a top plan view of my novel rheostat. I s

Fig. 2 represents a bottom plan View.

Fig. 8 is a crosssectional view, taken on the line 33 Off Fig. 1, looking in the direction of the arrows.

Fig. 4 is a cross-sectional view, taken on the line 4-at of Fig. 3,.looking in the direction of the arrows;

There are many forms of rheostats in the prior art, and the principle of operation of my novel device is similar to many of those I have, however, produced a forproduction under modern manufacturing methods, where each part is turned out in large quantities. I have constructed a rheostat comprising relatively few parts, which may be quickly and easily assembled into the completed device.

Referring to the drawings, the main support 1, is formed of thin metal or other suitable material in the shape of a T, and comprises the two arms 2 and 3, as shown in the drawings. The free end of theportion 1, is provided with tabs 4 and 5 by punching out a portion of the material to leave these tabs. The free ends of the portions 2 and 3 are bent up at right angles to form the projections 7 and 8, respectively. A strip of insulating material 13, such as fibre, is wound with any suitable resistance wire 14, as shown, and is secured to the T support by means of the tabs 4 and 5 between which the resistance element is clamped after it has been covered by means of a piece of insulatnig material 6. The free ends of the resistance element are clamped to the upturned ends of the portions 2 and 3, by means oi eye rivetsilandlO respectively. A small piece of insulating material is clamped also by means of the rivet 10, to the resistance unit, and has a small projection, as shown in Fig. 3, to provide a stop for the movable arm. A terminal clip 12 is clamped between the insulating strip 13 and the upturned portion of the arm 2, to provide electrical connection with the support 1. By means of the eye rivets 16, another short terminal member 15 is secured to the insulating strip 13, and is in contact with thei ree end of the resistance wire 14, which encircles the msulating strip, and which terminates at this point. Secured to the T-shaped support 1, as shown, is a contacting arm 17, which is pivotally supported on the hollow post 18, which is, in turn, secured to the T-shaped support by means or the flanged portion 19. A short shaftprojects through the post 18, and has riveted thereto the contacting arm 17, as shown at 20. The shortshaft 20 is provided with notches 21, and may be threaded, if desired, so that an operating knob, not shown, may be secured thereto.

The current will pass through'the device by means of a wire attached to the terminal 15, through the resistance wire to the particular point at which the arm may be resting, thence through the arm and supporting post to the Tshaped member, and finally to the terminal clip 12, which is in contact therewith. If desired, the resistance wire may be interrupted near the point where the resistance unit is attached to the arm 3, so' that no current can travel to the support at this point.

It will be seen from the foregoing description that I have provided a very simple rheostat construction which is readily adapted for quantity production. I do not, however, desire to be limited to the exact construction disclosed by me, but rather to my invention as I have defined it in the following claim, since I am aware that changes in detail of construction and arrangement of parts Will suggest themselves to those skilled in the art.

What I seek to secure by United States Letters Patent, is:

In a rheostat, the combination with a'support having upturned ends, of a resistance unit secured to said ends, an arm for contacting With said unit, a hollow post secured to 10 said support, means for securing said arm to said post, said means being slotted to receive actuating means, and current terminals secured to said support and unit.

In testimony whereof I have hereunto set my hand on this fourth day of November,

A. D. 1926. a

ARTHUR O. BRADY. 

